The Company arrives on the other side of the river, and the Men that accompanied them head back to Lake-town. The Dwarves search the mountainside for the secret door, and Fili, Kili, and Bilbo eventually find it. At the end of Durin's Day, a Thrush knocks on a nearby rock, and, exactly as the moon letters on the map predicted, the last light of the setting sun reveals the hidden keyhole. Bilbo reminds Thorin of the key, and the door is opened.

As they approach the foothills of the Lonely Mountain, the land turns bleak and barren. All greenery and other living foliage have been burnt away by Smaug. When they arrive, Bilbo and three dwarves are sent to investigate the main entrance on the south side. The entrance looks far too dangerous (it is the gate that Smaug uses), so the Company decides to search out the secret door described on their map, which is on the west side of the mountain.

After hours of searching, Bilbo finally locates a narrow passage along a cliff that leads to a flat, smooth patch on the mountain’s side. Though the patch must be the door, the dwarves cannot find a way to open it, as they have forgotten the message that Elrond read from the map. The dwarves bang at the door with picks and axes, but to no avail.

One evening, Bilbo is sitting outside the door when a thrush lands nearby and begins to knock a snail against a stone with its beak. Suddenly, he remembers the riddle on the map. He quickly gathers the other dwarves by the door, and they watch as the sun slowly sets. With the sun’s last light, a single ray falls on part of the door, and a rock falls away to reveal a keyhole. Thorin takes the key that came with the map and places it in the rock. The dwarves and the hobbit push open the door and stare into the depths of the mountain before them.